<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        :is(.h1,.h2):hover{
            color: aqua;
            cursor: pointer;
        }
        /* p标签但不包括类名为header的元素 */
        p:not(.header){ 
            color: red;
        }
    </style>
</head>
<body>
    <div class="h1">111</div>
    <div class="h2">222</div>
    <p>第一行</p>
    <p class="header">第二行</p>
    <p>第三行</p>
    <p class="header">第四行</p>
    <p>第五行</p>
</body>
</html>